CASH, CASH EQUIVALENTS, AND INVESTMENTS

The following tables summarize the Company’s cash and available-for-sale securities’ adjusted cost, gross unrealized gains, gross unrealized losses, and fair value by significant investment category recorded as cash and cash equivalents, short-term, or long-term investments as of December 31, 2015 and March 31, 2015 (in thousands):



December 31, 2015	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value		Cash & Cash Equivalents		Short-term investments (due in 1 year or less)		Long-term investments (due in 1 to 3 years)
Cash	$	209,379	$	—	$	—		$	209,379	$	209,379	$	—	$	—
Level 1:
Mutual Funds	9,497		1		(546		)	8,952		—		8,952		—
US Treasury Notes	39,822		—		(96		)	39,726		4,006		16,000		19,720
Subtotal	49,319		1		(642		)	48,678		4,006		24,952		19,720
Level 2:
Government Agency Securities	70,680		1		(178		)	70,503		—		20,919		49,584
Commercial Paper	40,196		—		—			40,196		4,199		35,702		295
Corporate Bonds	143,139		22		(375		)	142,786		—		77,221		65,565
Certificates of Deposits ("CDs")	8,970		—		—			8,970		1,507		7,463		—
Subtotal	262,985		23		(553		)	262,455		5,706		141,305		115,444

Total cash, cash equivalents and investments measured at fair value	$	521,683	$	24	$	(1,195	)	$	520,512	$	219,091	$	166,257	$	135,164



March 31, 2015	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value		Cash & Cash Equivalents		Short-term investments (due in 1 year or less)		Long-term investments (due in 1 to 3 years)
Cash	$	273,350	$	—	$	—		$	273,350	$	273,350	$	—	$	—
Level 1:
Mutual Funds	5,398		147		(25		)	5,520		—		5,520		—
Level 2:
Government Agency Securities	89,875		37		(22		)	89,890		—		43,024		46,866
Commercial Paper	17,574		10		—			17,584		3,500		14,084		—
Corporate Bonds	95,759		199		(3		)	95,955		—		35,231		60,724
Subtotal	203,208		246		(25		)	203,429		3,500		92,339		107,590

Total cash, cash equivalents and investments measured at fair value	$	481,956	$	393	$	(50	)	$	482,299	$	276,850	$	97,859	$	107,590

As of December 31, 2015 and March 31, 2015, with the exception of assets related to the Company's deferred compensation plan, all of the Company's investments are classified as available-for-sale securities. The carrying value of available-for-sale securities included in cash equivalents approximates fair value because of the short maturity of those instruments. For more information regarding the Company's deferred compensation plan, refer to Note 4, Deferred Compensation, of the accompanying notes to condensed consolidated financial statements (unaudited) in this Quarterly Report on Form 10-Q.

The Company did not incur any material realized or unrealized gains or losses in the three and nine months ended December 31, 2015 and 2014.

There were no transfers between fair value measurement levels during the three and nine months ended December 31, 2015 and 2014.

All financial assets and liabilities are recognized or disclosed at fair value in the financial statements or the accompanying notes thereto. Fair value is estimated by applying the following hierarchy, which prioritizes the inputs used to measure fair value into three levels and bases the categorization within the hierarchy upon the lowest level of input that is available and significant to the fair value measurement:

Level 1

The Company's Level 1 financial assets consist of Mutual Funds and US Treasury Notes. The fair value of Level 1 financial instruments is measured based on the quoted market price of identical securities.

Level 2

The Company's Level 2 financial assets and liabilities consist of Government Agency Securities, Commercial Paper, Corporate Bonds, and Certificates of Deposits ("CDs"), derivative foreign currency contracts, and long-term debt. The fair value of Level 2 investment securities is determined based on other observable inputs, including multiple non-binding quotes from independent pricing services. Non-binding quotes are based on proprietary valuation models that are prepared by the independent pricing services and use algorithms based on inputs such as observable market data, quoted market prices for similar securities, issuer spreads, and internal assumptions of the broker. The Company corroborates the reasonableness of non-binding quotes received from the independent pricing services using a variety of techniques depending on the underlying instrument, including: (i) comparing them to actual experience gained from the purchases and maturities of investment securities, (ii) comparing them to internally developed cash flow models based on observable inputs, and (iii) monitoring changes in ratings of similar securities and the related impact on fair value. The fair value of Level 2 derivative foreign currency contracts is determined using pricing models that use observable market inputs. For more information regarding the Company's derivative assets and liabilities, refer to Note 12, Foreign Currency Derivatives, of the accompanying notes to condensed consolidated financial statements (unaudited) in this Quarterly Report on Form 10-Q. The fair value of Level 2 long-term debt is determined based on inputs that were observable in the market, including the trading price of the notes when available. For more information regarding the Company's long-term debt, refer to Note 7, Debt, of the accompanying notes to condensed consolidated financial statements (unaudited) in this Quarterly Report on Form 10-Q.